Journal articles: 'Control with laser pulses'

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Shemyakin, A. N., M. Yu Rachkov, N. G. Solov’ev, and M. Yu Yakimov. "Radiation Power Control of the Industrial CO₂ Laser Excited by а Nonself-Sustained Glow Discharge by Changing the Frequency of Ionization Pulses." Mekhatronika, Avtomatizatsiya, Upravlenie 21, no. 4 (April 11, 2020): 224–31. http://dx.doi.org/10.17587/mau.21.224-231.

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The article describes radiation power control of industrial CO2 lasers of Lantan series excited by а nonself-sustained glow discharge in the automatic mode. These lasers are closed-cycle fast gas-transport lasers excited by a nonself-sustained glow discharge with ionization by periodic-pulsed capacitively coupled auxiliary discharge. In this case, ionization and conductivity are provided by periodic-pulsed capacitively coupled discharge. The energy contribution to molecular oscillations is provided by the passage of the main discharge current through the plasma with electron density given by ionization. This permits easy laser power control, provides excellent optical homogeneity and stability of an active volume together with high laser efficiency. A system of a nonself-sustained glow discharge with ionization by periodic-pulsed capacitively coupled auxiliary discharge, the stages of creation and brief characteristics of the Lantan series lasers is presented. The method of controlling the power of laser radiation by changing the frequency of the ionization pulses is determined. This control method allows operating of the laser in continuous and in pulse-periodic modes with adjustable pulse ratio and pulse duration, and also provides switching from one mode to another. In the continuous mode, the radiation power is controlled by changing the frequency of ionization pulses, which are high voltage pulses with duration of 100 ns, given with the frequency of 1-5 kHz. Pulse-periodic radiation control is performed by modulating ionization pulses that consists of pulses being delivered in batches. The frequency of the pulses in a batch determines the radiation power in a pulse. The frequency of the batches following is the frequency of the pulse mode, and the length of the batch determines the pulses duration. Based on the experimental data, the dependence of the radiation power on the ionization pulses frequency was determined. An experimental system is presented and the measuring accuracy of the laser radiation power and the frequency of ionization pulses is determined. Data acquiring and processing of experimental results were performed using the NI 6008 USB data acquisition device in the LabVIEW programs of National Instruments. To study the dependence of the laser power on Мехатроника, автоматизация, управление, Том 21, № 4, 2020 231 the frequency of the ionization pulses, a regression analysis method was applied. Studies have shown that the dependence of the laser power on the ionization pulses frequency is linear in a wide range of parameters. The equation of the direct regression is calculated. The confidence estimates of the coefficients of the direct regression and the confidence estimates of the deviation of the theoretical direct regression from the empirical one are calculated with a confidence level of 95%.

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Petkovšek, Rok, Vid Agrež, Jaka Petelin, Luka Černe, Udo Bünting, and Boštjan Podobnik. "Pulses on Demand in Fibre and Hybrid Lasers." Strojniški vestnik – Journal of Mechanical Engineering 65, no. 11-12 (November 18, 2019): 680–89. http://dx.doi.org/10.5545/sv-jme.2019.6352.

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This paper presents an investigation of pulse-on-demand operation in fibre and hybrid lasers. Two methods for efficient gain control that enable the generation of laser pulses at arbitrary times with controlled pulse parameters are presented. The method of direct modulation of the pump power in the high-power laser oscillator is shown to generate pulses with a duration in the nanosecond range, with repetition rates varying during operation from a single shot to over 1 MHz. An advanced method using a combination of marker and idler seeding a fibre amplifier chain is investigated. Such a system can easily achieve repetition rates of several tens of MHz. The lasers’ performances were successfully tested in a real environment on an industrial platform for laser transfer printing. Similar concepts were used for a laser source with ultrashort laser pulses (femtosecond range) on demand by using a mode-locked seed as a source and a solid-state amplifier to achieve high pulse energy and peak power.

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Shirkhaghah, N., M. Saadati-Niari, and B. Nedaee-Shakarab. "Stark-shift-chirped rapid-adiabatic-passage technique in tripod systems." Revista Mexicana de Física 67, no. 2 Mar-Apr (July 15, 2021): 180–87. http://dx.doi.org/10.31349/revmexfis.67.180.

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We show that the technique of Stark-chirped rapid adiabatic passage (SCRAP), can be implemented in tripod quantum systems. We propose a scheme for coherent superposition among two ground states via Stark-shiftchirped rapid adiabatic passage technique in a tripod system. Tripod-SCRAP uses four laser pulses: an intense far-off-resonance Stark laser pulse modifies the transition frequency between the states by Stark shifting their energies and three nearly resonant pump, Stokes, and control laser pulses that fractionally transfer the population between the ground states via adiabatic passage. In our scheme, the pulse duration of the pump pulse must be larger than the pulse duration of the Stokes and control pulses, although with a smaller amplitude, and the atom encounters with the pump, Stokes, control, and Stark laser pulses with counterintuitive order (Stokes pulse arrives before the rest of the pulses). This technique can be applied to one-photon as well as multiphoton transitions and it is not necessary to vanish the pulses (pump and Stokes) simultaneously and it is a powerful alternative tool for f-STIRAP and tripod-STIRAP techniques at least when inhomogeneous broadenings are included. inhomogeneous broadening. This technique is robust against moderate variations in the intensities of the laser pulses,in detunings, and in delays between the pulses.

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Zhao, Lu, Antoine Normand, Jonathan Houard, Ivan Blum, Fabien Delaroche, Olivier Latry, Blaise Ravelo, and Francois Vurpillot. "Optimizing Atom Probe Analysis with Synchronous Laser Pulsing and Voltage Pulsing." Microscopy and Microanalysis 23, no. 2 (February 8, 2017): 221–26. http://dx.doi.org/10.1017/s1431927616012666.

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AbstractAtom probe has been developed for investigating materials at the atomic scale and in three dimensions by using either high-voltage (HV) pulses or laser pulses to trigger the field evaporation of surface atoms. In this paper, we propose an atom probe setup with pulsed evaporation achieved by simultaneous application of both methods. This provides a simple way to improve mass resolution without degrading the intrinsic spatial resolution of the instrument. The basic principle of this setup is the combination of both modes, but with a precise control of the delay (at a femtosecond timescale) between voltage and laser pulses. A home-made voltage pulse generator and an air-to-vacuum transmission system are discussed. The shape of the HV pulse presented at the sample apex is experimentally measured. Optimizing the delay between the voltage and the laser pulse improves the mass spectrum quality.

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Barna, A., I. B. Földes, Z. Gingl, and R. Mingesz. "Compact Energy Measuring System for Short Pulse Lasers." Metrology and Measurement Systems 20, no. 2 (June 1, 2013): 183–90. http://dx.doi.org/10.2478/mms-2013-0016.

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Abstract In experiments with short-pulse lasers the measurement control of the energy of the laser pulse is of crucial importance. Generally it is difficult to measure the amplitude of the pulses of short-pulse lasers using electronic devices, their response time being longer than the duration of the laser pulses. The electric response of the detector is still too fast to be directly digitized therefore a peak-hold unit can be used to allow data processing for the computer. In this paper we present a device which measures the energy of UV short (fs) pulses shot-byshot, digitizes and sends the data to the PC across an USB interface. The circuit is based on an analog peak detect and hold unit and the use of fiber optical coupling between the PC and the device provides a significant improvement to eliminate potential ground loops and to reduce conductive and radiated noise as well. The full development is open source and has been made available to download from our web page (http://www.noise.inf.u-szeged.hu/Instruments/PeakHold/).

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CHEN, SHUJUN, YAZHOU JIA, WENHAO HUANG, and JUN XIAO. "Laser-Driven Programmable Metal Transfer in GMAW." Welding Journal 99, no. 3 (March 1, 2020): 93s—100s. http://dx.doi.org/10.29391/2020.99.009.

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Conventional pulsed laser-enhanced gas metal arc weld-ing (GMAW) employs a single fiber laser focused and aimed on the droplet neck position to produce a laser recoil force and thus ensure the droplet detachment despite the am-perage of the welding current. One drop per laser pulse metal transfer is obtained, and the droplet deflects away from the wire axis along the laser incident direction. This implies that the droplet trajectory may also be controlled if the direction of the laser recoil force can be adjusted. Such a controllability is expected to bring an entirely new capa-bility to the GMAW process: active control on the weld beam geometry. To this end, double-sided, laser-enhanced GMAW was proposed and experimentally verified in this pa-per. The two lasers were symmetrically positioned, and both aimed at the droplet neck. The laser pulse peak power, du-ration, and pulse phase of the two lasers can all be programmed to regulate the laser recoil forces. The metal transfer under twin laser irradiations (same laser pulses and phases) was first verified. Then the effectiveness on controlling the droplet trajectory of three proposed control strategies — peak power matching, peak width matching, and phase matching of the two lasers — were evaluated. The results showed laser peak power matching is optimal for obtaining desired droplet trajectory. Since the laser can be easily controlled in real time, the transfer frequency, droplet size, and trajectory can all be adjusted in real time, and the metal transfer evolves into programmable transfer.

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Meyer, Kristina, Zuoye Liu, Niklas Müller, Jan-Michael Mewes, Andreas Dreuw, Tiago Buckup, Marcus Motzkus, and Thomas Pfeifer. "Signatures and control of strong-field dynamics in a complex system." Proceedings of the National Academy of Sciences 112, no. 51 (December 8, 2015): 15613–18. http://dx.doi.org/10.1073/pnas.1509201112.

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Controlling chemical reactions by light, i.e., the selective making and breaking of chemical bonds in a desired way with strong-field lasers, is a long-held dream in science. An essential step toward achieving this goal is to understand the interactions of atomic and molecular systems with intense laser light. The main focus of experiments that were performed thus far was on quantum-state population changes. Phase-shaped laser pulses were used to control the population of final states, also, by making use of quantum interference of different pathways. However, the quantum-mechanical phase of these final states, governing the system’s response and thus the subsequent temporal evolution and dynamics of the system, was not systematically analyzed. Here, we demonstrate a generalized phase-control concept for complex systems in the liquid phase. In this scheme, the intensity of a control laser pulse acts as a control knob to manipulate the quantum-mechanical phase evolution of excited states. This control manifests itself in the phase of the molecule’s dipole response accessible via its absorption spectrum. As reported here, the shape of a broad molecular absorption band is significantly modified for laser pulse intensities ranging from the weak perturbative to the strong-field regime. This generalized phase-control concept provides a powerful tool to interpret and understand the strong-field dynamics and control of large molecules in external pulsed laser fields.

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MINGESZ, ROBERT, ANGELA BARNA, ZOLTAN GINGL, and JANOS MELLAR. "ENHANCED CONTROL OF EXCIMER LASER PULSE TIMING USING TUNABLE ADDITIVE NOISE." Fluctuation and Noise Letters 11, no. 01 (March 2012): 1240007. http://dx.doi.org/10.1142/s021947751240007x.

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Recently we have shown a system developed to precisely control the laser pulse timing of excimer lasers [R. Mingesz, Z. Gingl, G. Almasi, A. Csengeri and P. Makra, Utilising jitter noise in the precise synchronisation of laser pulses, Fluct. Noise Lett. 8 (2008) L41–L49]. The electronic circuit based on an embedded microcontroller and utilized the natural jitter noise of the laser pulse generation to improve the long term regulation of the delay of the laser related to an external trigger pulse. Based on our results we have developed an improved system that uses additional, programmable time delay units to tune the noise source to further enhance performance and allows reduction of complexity in the same time. A mixed-signal microcontroller generates a randomly dithered delay of the pulse generation moment to enhance the resolution and also runs a dedicated algorithm to optimize regulation. The compact, flexible hardware supports further enhancements; the signal processing algorithm can be replaced even by in-system reprogramming. Optimized processing and the relaxed hardware requirements may also support low-power operation, wireless communication, therefore the application possibilities may be extended to many other disciplines.

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SUDA, Akira, and Fumihiko KANNARI. "Spatial and Temporal Laser Pulse Control Technologies for Applications of Intense Laser Pulses." Review of Laser Engineering 37, no. 6 (2009): 408–19. http://dx.doi.org/10.2184/lsj.37.408.

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Yu, Xi, Fumihiro Itoigawa, and Shingo Ono. "Femtosecond Laser-Pulse-Induced Surface Cleavage of Zinc Oxide Substrate." Micromachines 12, no. 6 (May 21, 2021): 596. http://dx.doi.org/10.3390/mi12060596.

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The induction of surface cleavage along the crystalline structure of a zinc oxide substrate (plane orientation: 0001) by femtosecond laser pulses (wavelength: 1030 nm) has been reported; a scanning electron microscope image of the one-pulse (pulse energy: 6–60 μJ) irradiated surface shows very clear marks from broken hexagons. This cleavage process differs from the general laser-induced melt process observed on the surfaces of narrower-bandgap semiconductors and other metal materials. This phenomenon is discussed using a multi-photon absorption model, and the pulse-energy dependence of the cleavage depth (less than 3 μm) is quantitatively analyzed. Laser-induced cleavage is found not to occur under multi-pulse irradiation; when more than four pulses are irradiated upon the same spot, the general laser-induced melt process becomes dominant. This cleavage–melt shift is considered to be caused by the enhancement of absorption due to the initial pulses, which is supported by our measurement of cathodoluminescence.

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Carlson, David R., Daniel D. Hickstein, Wei Zhang, Andrew J. Metcalf, Franklyn Quinlan, Scott A. Diddams, and Scott B. Papp. "Ultrafast electro-optic light with subcycle control." Science 361, no. 6409 (September 27, 2018): 1358–63. http://dx.doi.org/10.1126/science.aat6451.

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Light sources that are ultrafast and ultrastable enable applications like timing with subfemtosecond precision and control of quantum and classical systems. Mode-locked lasers have often given access to this regime, by using their high pulse energies. We demonstrate an adaptable method for ultrastable control of low-energy femtosecond pulses based on common electro-optic modulation of a continuous-wave laser light source. We show that we can obtain 100-picojoule pulse trains at rates up to 30 gigahertz and demonstrate sub–optical cycle timing precision and useful output spectra spanning the near infrared. Our source enters the few-cycle ultrafast regime without mode locking, and its high speed provides access to nonlinear measurements and rapid transients.

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Aquila, A., M. Drescher, T. Laarmann, M. Barthelmeß, H. N. Chapman, and S. Bajt. "Moving the Frontier of Quantum Control into the Soft X-Ray Spectrum." International Journal of Optics 2011 (2011): 1–4. http://dx.doi.org/10.1155/2011/417075.

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The femtosecond nature of X-ray free electron laser (FEL) pulses opens up exciting research possibilities in time-resolved studies including femtosecond photoemission and diffraction. The recent developments of seeding X-ray FELs extend their capabilities by creating stable, temporally coherent, and repeatable pulses. This in turn opens the possibility of spectral engineering soft X-ray pulses to use as a probe for the control of quantum dynamics. We propose a method for extending coherent control pulse-shaping techniques to the soft X-ray spectral range by using a reflective geometry 4f pulse shaper. This method is based on recent developments in asymmetrically cut multilayer optic technology and piezoelectric substrates.

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Zhou, JianYing, JianHua Zeng, and JunTao Li. "Quantum coherent control of ultrashort laser pulses." Chinese Science Bulletin 53, no. 5 (March 2008): 652–58. http://dx.doi.org/10.1007/s11434-008-0050-x.

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Umanskaya, Sofia Filippovna, Pavel Aleksandrovich Danilov, Seigey Ivanovich Kudryashov, Andrey Andreevich Rudenko, and Andrey Alekseevich Ionin. "Wetting Control in the Layered Polymer-silver Thin Film via Femtosecond Laser Microstructuring." Communications in Physics 29, no. 1 (March 18, 2019): 71. http://dx.doi.org/10.15625/0868-3166/29/1/13503.

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Water wetting of a structured multi-layered thin film consisting of bottom silver and top polymer layers microstructured by femtosecond laser pulses was studied. The periodic trenches were ablatively produced on the top polymer layer of the film using 515-nm, 220-fs pulses of an ytterbium-doped fiber laser at different pulse energies and the repetition rate of 20 kHz. The topography of the structured film was observed by means of a JEOL 7001F scanning electron microscope and its water wetting angles were measured by side-view microscopic imaging. The wetting angle on the microstructured surface was 144°, comparing to 83° at the raw unstructured surface of the film.

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Minko, D. V. "Influence of parameters of impulse laser impact on the formation of the gradient of the structure of porous titanium powder." Litiyo i Metallurgiya (FOUNDRY PRODUCTION AND METALLURGY), no. 3 (October 5, 2018): 88–94. http://dx.doi.org/10.21122/1683-6065-2018-3-88-94.

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The possibility of selective laser sintering of graded porous and compactly porous structures by surface fusion of powder particles is demonstrated while maintaining a solid core, which leads to the formation of interparticle contacts in the presence of a liquid phase. The interaction of the light flux of the laser pulse with the surface of the powder particles under multiple reflection is considered. It is shown that the effect of single pulses of laser radiation leads to the formation of sintered structural elements of a powder material having a diameter approximately equal to the diameter of the focal spot. Technological regimes of pulsed laser action are established at which steady contact formation of titanium powder particles of the fractional compositions under study occurs. The possibility of obtaining powder materials with a gradient structure by controlling the parameters of pulsed laser action is experimentally demonstrated. It was found that accurate dosing of thermal energy and the number of pulses of laser radiation makes it possible to minimize shrinkage of powder layers in the absence of particle conglomeration, to control the structural characteristics and properties of products, to preserve the microstructure and phase composition of the initial materials.

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Yuan, Dong Qing, and Jian Ting Xu. "Periodic Nanostructure on 65Mn Produced by Femtosecond Laser Irradiation." Advanced Materials Research 154-155 (October 2010): 490–93. http://dx.doi.org/10.4028/www.scientific.net/amr.154-155.490.

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The periodic microstructures on 65Mn plate were induced by the irradiation of the femtosecond laser with the laser wavelength of 800 nm and the pulse length of 130 fs. The parallel periodic ripples structures were observed at the laser fluence of 1 J/cm2 with different pulses number( N=5,50,400,800) which lied parallel to the laser electric polarization field vector. For 400 pulses, the nano-holes arrays were generated to interrupt the consistent ripples structures.For 800 pulses, initial nano-holes evolution to the grooves, which the direction were uncertainly. Further experiments have been made to induce large area consitent ripple structures by scanning, at the laser fluence of 1 J/cm2 with speed v=500μm/s. 2D arrays were induced by accurate processing control

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17

Hess, Wayne P., Alan G. Joly, Daniel P. Gerrity, Kenneth M. Beck, Peter V. Sushko, and Alexander L. Shluger. "Control of laser desorption using tunable single pulses and pulse pairs." Journal of Chemical Physics 116, no. 18 (May 8, 2002): 8144–51. http://dx.doi.org/10.1063/1.1467345.

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Kojima, Yasuhiro, Yuta Masaki, and Fumihiko Kannari. "Control of ultrafast plasmon pulses by spatiotemporally phase-shaped laser pulses." Journal of the Optical Society of America B 33, no. 12 (November 10, 2016): 2437. http://dx.doi.org/10.1364/josab.33.002437.

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Bandrauk, André D., and Heng Tai Yu. "Laser control of molecular ionization with intense short laser pulses." International Journal of Mass Spectrometry 192, no. 1-3 (September 1999): 379–86. http://dx.doi.org/10.1016/s1387-3806(99)00114-1.

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20

Malinovsky, V. S., and I. R. Sola. "Phase control for entanglement preparation in two-qubit systems." Quantum Information and Computation 5, no. 4&5 (July 2005): 364–79. http://dx.doi.org/10.26421/qic5.45-7.

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The theory of Quantum Control is starting to lay bridges with the field of Quantum Information and Quantum Computation. Using key ideas of laser control of the dynamics by means of phase manipulation and adiabatic passage, we review laser schemes that allow entanglement preparation in a two-qubit system. The schemes are based on sequences that use four time-delayed pulses, with or without concerted decay, in or off resonance with the intermediate levels of the qubit space. We show how to control the fidelity and phase of the entanglement, as well as the sensitivity of the preparation to the different pulse parameters. In general the schemes provide an improvement in robustness and in the finesse of the control to phase, with respect to previously proposed schemes based on sequences of $\pi$ pulses.

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Semaan, G., F. Ben Braham, M. Salhi, and François Sanchez. "Roadmap to high-energy square pulses in anomalous dispersion fiber lasers." Photonics Letters of Poland 8, no. 4 (December 31, 2016): 95. http://dx.doi.org/10.4302/plp.2016.4.02.

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Dissipative soliton resonance (DSR) is a soliton formation where the energy in a dissipative system becomes infinite. In the anomalous dispersion regime, this energy is not limited by the soliton area theorem. Since this phenomenon is wave breaking free, it can be useful in designing fiber lasers generating pulses with relatively high energies. Based on this principle, we have demonstrated the emission of high energetic square pulses from Er:Yb double-clad passively mode-locked fiber lasers using different mode-locking mechanisms. We first show the evolution of pulse width, energy and peak power by varying the pumping power of the amplifier, then we control separately the characteristic of the output square pulse by assigning each one to an amplifier. Experimental results exhibit record energies in fiber lasers up to 10 uJ. Full Text: PDF ReferencesW. Chang, A. Ankiewicz, J.M Soto Crespo and N. Akhmediev, " Dissipative soliton resonances", Phys. Rev. A 78, 023830 (2008). CrossRef P. Grelu, W. Chang, A. Ankiewicz, J. M. Soto-Crespo, and N. Akhmediev, "Dissipative soliton resonance as a guideline for high-energy pulse laser oscillators", J. Opt. Soc. Am. B 27, 2336 (2010). CrossRef X. Wu, D. Y. Tang, H. Zhang, and L. M. Zhao, "Dissipative soliton resonance in an all-normal-dispersion erbium-doped fiber laser", Opt. Express 17, 5580 (2009). CrossRef G. Semaan, F. Ben Braham, M. Salhi, Y. Meng, F. Bahloul, and F. Sanchez, "Generation of high energy square-wave pulses in all anomalous dispersion Er:Yb passive mode locked fiber ring laser", Opt. Express 24, 8399 (2016). CrossRef K. Krzempek, "Dissipative soliton resonances in all-fiber Er-Yb double clad figure-8 laser", Opt. Express 23, 30651 (2015). CrossRef L. Mei et al., "Width and amplitude tunable square-wave pulse in dual-pump passively mode-locked fiber laser", Opt. Lett. 39, 3235 (2014). CrossRef X. Zhang et al., "Square-wave pulse with ultra-wide tuning range in a passively mode-locked fiber laser", Opt. Lett. 37, 1334 (2012). CrossRef K. Krzempek, J. Sotor, and K. Abramski, "Compact all-fiber figure-9 dissipative soliton resonance mode-locked double-clad Er:Yb laser", Opt. Lett. 41, 4995-4998 (2016). CrossRef G. Semaan, F. Ben Braham, J. Fourmont, M. Salhi, F. Bahloul, and F. Sanchez, "10uJ dissipative soliton resonance square pulse in a dual amplifier figure-of-eight double-clad Er:Yb mode-locked fiber laser", Opt. Lett. 41, 4767 (2016). CrossRef K. Krzempek and K. Abramski, "Dissipative soliton resonance mode-locked double clad Er:Yb laser at different values of anomalous dispersion", Opt. Express 24, 22379-22386 (2016). CrossRef

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Al-Juboory, Karim H., David J. Williams, and M. H. Nayfeh. "THE EFFECT OF PULSED EXCIMER LASER RADIATION ON CONTROL OF IN VITRO CULTURE CONTAMINATION AND THE GROWTH OF HEDERA CANARIENSIS." HortScience 25, no. 9 (September 1990): 1150a—1150. http://dx.doi.org/10.21273/hortsci.25.9.1150a.

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This study was initiated to investigate the effect of pulsed XeCL excimer laser radiation (308 nm) at 25 and 50 pulses per second at radiation levels of 0, 100 mJ, 200 mJ, and 300 mJ on microorganism contamination of in vitro cultures of Heder a canariensis. Explants were cultured on Murashige and Skoog (MS) medium supplemented with 8 mg/BA and 0.2 mg/NAA. The medium was adjusted to pH 5.7. The cultures were maintained for 16-hours photoperiods at 25.5°C. One day following transfer the explants were treated with pulsed excimer laser radiation. The percentage of contamination was reduced by laser radiation treatments. The effect of 5 0 pulses of radiation was found to increase the petiole length, leaf blade width, and leaf number of explants.

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Wang, Ling, Bo Mo, and Ke Gao. "A New Design of Laser Pulse Receiver in the Automatic Control System." Applied Mechanics and Materials 496-500 (January 2014): 1434–37. http://dx.doi.org/10.4028/www.scientific.net/amm.496-500.1434.

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The existing problem of current laser pulse receiving system is that the laser pulses width is too narrow to be directly collected. And the consistency of the four signals acquisition is very strict. To deal with these problems, a new design of laser pulse receiver will be introduced in this article. This laser pulse receiving system includes the following structures: new high-speed laser pulse receiving hardware based on CPLD and Four-Quadrant Detectors, new peak-hold circuit of laser pulse, high-speed parallel ADC system, and processing data with fast interpolation algorithm in a Floating-Point DSP. Through the new design of high-speed parallel ADC system, the receiving system is able to simultaneously complete the timing of four high-speed laser pulse signals acquisition and the storing of data. The new construction of high-speed parallel acquisition is a core module in this design. And a new flow how to the DSP handle the data with fast interpolation algorithm will also be introduced in this article.

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Chen, Zhiwen, Yingying Yan, Jun Shu, Kefu Liu, and Jian Qiu. "Modulated High Power and Narrow Pulse Width Laser Drive Circuit for Lidar System." Electronics 10, no. 7 (March 30, 2021): 823. http://dx.doi.org/10.3390/electronics10070823.

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This manuscript introduces a laser drive circuit for a light detection and ranging (Lidar) system. A Lidar system usually requires its drive circuit to provide laser pulses with nanosecond pulse width, >100 W peak power and high repetition frequency. However, the existing research results show difficulties in meeting these requirements. In order to reduce the pulse width and increase the peak power of laser pulses, special circuit design and component selection are used to optimize the parasitic parameters of the drive circuit, and GaN devices are used to increase the switching speed. The characteristics of laser pulses are tested under different input voltage, pulse per second and switch conducting time. Meanwhile, the reasons for the changes in these characteristics are analyzed and explained. In order to meet the requirements of the Lidar system to detect targets at different distances, a modulation method to change the peak power of the laser pulse is proposed. In our experiment, ideally, the peak power of the laser pulse reaches 135 W, and the pulse width is less than 2 ns at a pulse per second rate of 400 kHz.

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Tan, Chao, Binliang Hu, Shiping Zhan, Yonghua Hu, and Bin Zhong. "All-Optical Switching Based on the Plasma Channel Induced by Laser Pulses." Advances in Condensed Matter Physics 2018 (October 1, 2018): 1–7. http://dx.doi.org/10.1155/2018/9621953.

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We display a theoretical and experimental study of all-optical switching for signal lasers based on the plasma channel induced by the control laser. Using the plasma channel generated in the carbon disulfide (CS2) solution, the signal light can be modulated as some spatial distributions including unchanging, ring-shaped beam, and other intensity profiles. The modulation on the signal light can be conveniently adjusted by changing the control light’s incident intensity distribution. We can infer the dark spot shape in the modulated signal laser through the intensity profile of control laser beam. These results provide the great potential of plasma channel induced by lasers as an all-optical switching for various optoelectronic applications.

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Wenjing Cheng, Wenjing Cheng, Shian Zhang Shian Zhang, Tianqing Jia Tianqing Jia, Jing Ma Jing Ma, Donghai Feng Donghai Feng, and Zhenrong Sun Zhenrong Sun. "Coherent control of two-photon absorption of Pr3+ ion by shaped ultrashort laser pulses." Chinese Optics Letters 11, no. 4 (2013): 041903–41906. http://dx.doi.org/10.3788/col201311.041903.

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Goswami, Debabrata, Dhiman Das, and Soumendra Nath Bandyopadhyay. "Resolution enhancement through microscopic spatiotemporal control." Faraday Discussions 177 (2015): 203–12. http://dx.doi.org/10.1039/c4fd00177j.

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Operating at biologically benign conditions, multi-photon fluorescence imaging microscopy has benefitted immensely from recent developments in microscopic resolution enhancement. Fluorescence microscopy continues to be the best choice for experiments on live specimens, however, multi-photon fluorescence imaging often suffers from overlapping fluorescence of typical dyes used in microscopy, limiting its scope. This limitation has been the focus of our research where we show that by making simple modifications to the laser pulse structure, it is possible to resolve these overlapping fluorescence complications. Specifically, by using pairs of femtosecond pulses with variable delay in place of single pulse excitation, we show controlled fluorescence excitation or suppression of one of the fluorophores over the other through wave-packet interferometry. Such an effect prevails even after the fluorophore coherence timescale, which effectively results in a higher spatial resolution. Here we extend the effect of our pulse-pair technique to microscopic axial resolution experiments and show that such pairs of pulses can also ‘enhance’ axial resolution.

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Zacharatos, Filimon, Ioannis Theodorakos, Panagiotis Karvounis, Simon Tuohy, Nuno Braz, Semyon Melamed, Ayala Kabla, et al. "Selective Laser Sintering of Laser Printed Ag Nanoparticle Micropatterns at High Repetition Rates." Materials 11, no. 11 (October 31, 2018): 2142. http://dx.doi.org/10.3390/ma11112142.

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The increasing development of flexible and printed electronics has fueled substantial advancements in selective laser sintering, which has been attracting interest over the past decade. Laser sintering of metal nanoparticle dispersions in particular (from low viscous inks to high viscous pastes) offers significant advantages with respect to more conventional thermal sintering or curing techniques. Apart from the obvious lateral selectivity, the use of short-pulsed and high repetition rate lasers minimizes the heat affected zone and offers unparalleled control over a digital process, enabling the processing of stacked and pre-structured layers on very sensitive polymeric substrates. In this work, the authors have conducted a systematic investigation of the laser sintering of micro-patterns comprising Ag nanoparticle high viscous inks: The effect of laser pulse width within the range of 20–200 nanoseconds (ns), a regime which many commercially available, high repetition rate lasers operate in, has been thoroughly investigated experimentally in order to define the optimal processing parameters for the fabrication of highly conductive Ag patterns on polymeric substrates. The in-depth temperature profiles resulting from the effect of laser pulses of varying pulse widths have been calculated using a numerical model relying on the finite element method, which has been fed with physical parameters extracted from optical and structural characterization. Electrical characterization of the resulting sintered micro-patterns has been benchmarked against the calculated temperature profiles, so that the resistivity can be associated with the maximal temperature value. This quantitative correlation offers the possibility to predict the optimal process window in future laser sintering experiments. The reported computational and experimental findings will foster the wider adoption of laser micro-sintering technology for laboratory and industrial use.

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Butkus, Simas, Vytautas Jukna, Domas Paipulas, Martynas Barkauskas, and Valdas Sirutkaitis. "Micromachining of Invar Foils with GHz, MHz and kHz Femtosecond Burst Modes." Micromachines 11, no. 8 (July 29, 2020): 733. http://dx.doi.org/10.3390/mi11080733.

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In this work, a burst mode laser is used for micromachining of 20 µm–250 µm thick Invar (Fe64/Ni36) foils. Holes were drilled by firing multiple pulses transversely onto the sample without moving the beam (percussion drilling). The utilized laser system generates a burst of a controllable number of pulses (at 1030 nm) with tunable pulse-to-pulse time spacing ranging from 200 ps to 16 ns. The sub-pulses within the burst have equal amplitudes and a constant duration of 300 fs that do not change regardless of the spacing in time between them. In such a way, the laser generates GHz to MHz repetition rate pulse bursts with a burst repetition rate ranging from 100 kHz to a single shot. Drilling of the material is compared with the non-burst mode of kHz repetition rate. In addition, we analyze the drilling speed and the resulting dependence of the quality of the holes on the number of pulses per burst as well as the average laser power to find the optimal micromachining parameters for percussion drilling. We demonstrate that the micromachining throughput can be of an order of magnitude higher when using the burst mode as compared to the best results of the conventional kHz case; however, excess thermal damage was also evident in some cases.

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Ghoreishi, M., D. K. Y. Low, and L. Li. "Statistical modelling of laser percussion drilling for hole taper and circularity control." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 216, no. 3 (March 1, 2002): 307–19. http://dx.doi.org/10.1243/0954405021519988.

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The aim of the present work is to investigate the effects of different variables and their interactions in laser percussion drilling and to understand the possibility of controlling simultaneously the two important characteristics of a laser drilled hole: taper and circularity. Six variables, namely the peak power, pulse width, pulse frequency, number of pulses, assist gas pressure and focal plane position, were selected as independent controllable factors. The response surface method was used to statistically analyse the process. For each variable, five levels were considered and the experiments were performed based on a central composite design. A fibre-optic delivered neodymium-doped yttrium aluminium garnet laser was used to laser percussion drill mild steel sheets with a thickness of 2.5mm. The entrance diameter, the taper and the ratio of maximum to minimum Feret diameter for the hole entrance (circularity) were considered as responses/outputs in order to evaluate the process performance in terms of hole taper and circularity. Statistical modelling was carried out to develop mathematical models to relate the responses (outputs) to the six independent variables through multiple regression. A complete analysis of variance (ANOVA) was performed to test the significance of the obtained coefficients at 1, 5 and 7 per cent levels of significance. The developed models were verified by experiments. The work has shown that the pulse width and peak power have significant effects on the hole diameter, hole taper and hole circularity. However, the pulse frequency has no effect on these three hole characteristics. The number of pulses has no significant effect on hole diameter and circularity but has a significant effect on hole taper.

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31

Fitzgerald, Richard. "Ultrashort Laser Pulses Can Control X-Ray Switch." Physics Today 55, no. 2 (February 2002): 16–18. http://dx.doi.org/10.1063/1.1461320.

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Coughlan, Matthew A., Mateusz Plewicki, and Robert J. Levis. "Parametric Spatio-Temporal Control of Focusing Laser Pulses." Optics Express 17, no. 18 (August 21, 2009): 15808. http://dx.doi.org/10.1364/oe.17.015808.

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Chao, Long Sun, and Yu Ru Chen. "Experimental Analysis for the Low-Temperature Growth of Poly-Si Films by Using Double Excimer Laser." Materials Science Forum 594 (August 2008): 299–305. http://dx.doi.org/10.4028/www.scientific.net/msf.594.299.

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This paper is to investigate a double splitting excimer laser technique for making poly Si films. In this research, a KrF excimer laser of 248 nm in wavelength is used to irradiate a-Si films of 0.1 m in thickness on glass substrate to produce poly-Si ones. The control parameters are laser intensity (200~500 mJ/cm2), laser pulse number (1~2 shots) and delay time between two shots (one nanosecond). Average grain sizes from SEM photos are used to analyze the effects of these parameters. Firstly, in the excimer laser experiment, different laser fluences are utilized to study the effect on the microstructure of the silicon film. Purely from the viewpoint of heat transfer, the Si film obtains more energy has the slower cooling or solidification rate, which results in the larger grain. From the experimental results, it can be found that the grain size increases until the laser fluence increases up to the critical value of complete melting, which limits the grain growth method of energy increase. In this work, a double-splitting-laser method is proposed. In the method, a laser pulse from an excimer laser is divided into two pulses by a beam splitter. The cyclic optical path is used to control the delay time of the second pulse. Optical mirrors and optical attenuators are utilized to adjust the energy density of these two laser pulses. The delay time between these two pulses is changeable and controlled in the order of nanosecond. The second pulse is applied when the Si film is solidifying after the irradiation of the first one. This could enhance the solidification time and enlarge the grain size of the poly-Si film.

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Liu, ChunMei, Joern Manz, and Jean Christophe Tremblay. "From Symmetry Breaking via Charge Migration to Symmetry Restoration in Electronic Ground and Excited States: Quantum Control on the Attosecond Time Scale." Applied Sciences 9, no. 5 (March 6, 2019): 953. http://dx.doi.org/10.3390/app9050953.

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This article starts with an introductory survey of previous work on breaking and restoringthe electronic structure symmetry of atoms and molecules by means of two laser pulses. Accordingly,the first pulse breaks the symmetry of the system in its ground state with irreducible representationIRREPg by exciting it to a superposition of the ground state and an excited state with differentIRREPe. The superposition state is non-stationary, representing charge migration with period T inthe sub- to few femtosecond time domains. The second pulse stops charge migration and restoressymmetry by de-exciting the superposition state back to the ground state. Here, we present a newstrategy for symmetry restoration: The second laser pulse excites the superposition state to the excitedstate, which has the same symmetry as the ground state, but different IRREPe. The success dependson perfect time delay between the laser pulses, with precision of few attoseconds. The new strategyis demonstrated by quantum dynamics simulation for an oriented model system, benzene.

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Liu, Y., F. Y. Li, M. Zeng, M. Chen, and Z. M. Sheng. "Ultra-intense attosecond pulses emitted from laser wakefields in non-uniform plasmas." Laser and Particle Beams 31, no. 2 (May 2, 2013): 233–38. http://dx.doi.org/10.1017/s0263034613000220.

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AbstractA scheme of generating ultra-intense attosecond pulses in ultra-relativistic laser interaction with under-dense plasmas is proposed. The attosecond pulse emission is caused by an oscillating transverse current sheet formed by an electron density spike composed of trapped electrons in the laser wakefield and the residual transverse momentum of electrons left behind the laser pulse when its front is strongly modulated. As soon as the attosecond pulse emerges, it tends to feed back to further enhance the transverse electron momentum and the transverse current. Consequently, the attosecond pulse is enhanced and developed into a few cycles later until the density spike is depleted out due to the pump laser depletion. To control the formation of the transverse current sheet, a non-uniform plasma slab with an up-ramp density profile in front of a uniform region is adopted, which enables one to obtain attosecond pulses with higher amplitudes than that in a uniform plasma slab.

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Gusarov and Kovalev. "Sequences of Sub-Microsecond Laser Pulses for Material Processing: Modeling of Coupled Gas Dynamics and Heat Transfer." Applied Sciences 9, no. 22 (November 8, 2019): 4785. http://dx.doi.org/10.3390/app9224785.

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Multipulse laser processing of materials is promising because of the additional possibilities to control the thickness of the treated and the heat-affected zones and the energy efficiency. To study the physics of mutual interaction of pulses at high repetition rate, a model is proposed where heat transfer in the target and gas-dynamics of vapor and ambient gas are coupled by the gas-dynamic boundary conditions of evaporation/condensation. Numerical calculations are accomplished for a substrate of an austenitic steel subjected to a 300 ns single pulse of CO2 laser and a sequence of the similar pulses with lower intensity and 10 μs inter-pulse separation assuring approximately the same thermal impact on the target. It is revealed that the pulses of the sequence interact due to heat accumulation in the target but they cannot interact through the gas phase. Evaporation is considerably more intensive at the single-pulse processing. The vapor is slightly ionized and absorbs the infrared laser radiation by inverse bremsstrahlung. The estimated absorption coefficient and the optical thickness of the vapor domain are considerably greater for the single-pulse regime. The absorption initiates optical breakdown and the ignition of plasma shielding the target from laser radiation. The multipulse laser processing can be applied to avoid plasma ignition.

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Simon, Brady T., Joshua Dupaty, Ei Ei Brown, and Makhin Thitsa. "Model-free precision control of 808 nm laser pulses." MRS Advances 4, no. 11-12 (2019): 683–88. http://dx.doi.org/10.1557/adv.2019.71.

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ABSTRACTWe propose a method for precision control of the temporal pulse shape in 808 nm emission from Er-doped fluoroindate glasses. Previously, authors have reported the model based controller design, in which the controller varies and controls the pump rate in real time through the pump power. In model-based design, the performance of the resultant controller depends on the accuracy of the mathematical model used to represent the device in the design process. In this paper a more robust control scheme using model-free approach is presented. Specifically, the controller design is independent of the mathematical model and hence any modeling error has no effect on the device performance. This robustness against modeling error is critical for control purposes in optical materials where various up-conversion parameters are unknown or hard to determine with certainty.

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Haase, Dietrich, Gunter Hermann, Jörn Manz, Vincent Pohl, and Jean Christophe Tremblay. "Electron Symmetry Breaking during Attosecond Charge Migration Induced by Laser Pulses: Point Group Analyses for Quantum Dynamics." Symmetry 13, no. 2 (January 27, 2021): 205. http://dx.doi.org/10.3390/sym13020205.

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Quantum simulations of the electron dynamics of oriented benzene and Mg-porphyrin driven by short (<10 fs) laser pulses yield electron symmetry breaking during attosecond charge migration. Nuclear motions are negligible on this time domain, i.e., the point group symmetries G = D6h and D4h of the nuclear scaffolds are conserved. At the same time, the symmetries of the one-electron densities are broken, however, to specific subgroups of G for the excited superposition states. These subgroups depend on the polarization and on the electric fields of the laser pulses. They can be determined either by inspection of the symmetry elements of the one-electron density which represents charge migration after the laser pulse, or by a new and more efficient group-theoretical approach. The results agree perfectly with each other. They suggest laser control of symmetry breaking. The choice of the target subgroup is restricted, however, by a new theorem, i.e., it must contain the symmetry group of the time-dependent electronic Hamiltonian of the oriented molecule interacting with the laser pulse(s). This theorem can also be applied to confirm or to falsify complementary suggestions of electron symmetry breaking by laser pulses.

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Feng, Liqiang, and Hang Liu. "Laser control for harmonic selective enhancement." Canadian Journal of Physics 92, no. 12 (December 2014): 1592–98. http://dx.doi.org/10.1139/cjp-2013-0470.

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We theoretically investigate harmonic-selective enhancement by controlling the time-delayed two-color laser field. By properly controlling the delay times of the two pulses, selective enhancement of the harmonics with photon energies between 75 and 125 eV can be obtained, resulting in wavelength-tunable and bandwidth-controllable coherent extreme ultraviolet radiation. In addition, the other laser parameters’ effects on the harmonic-selective-enhancement have also been investigated.

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Kirilyuk, Andrei, Alexey V. Kimel, and Theo Rasing. "Controlling spins with light." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369, no. 1951 (September 28, 2011): 3631–45. http://dx.doi.org/10.1098/rsta.2011.0168.

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The interaction of sub-picosecond laser pulses with magnetically ordered materials has developed into an extremely exciting research topic in modern magnetism. From the discovery of sub-picosecond demagnetization over a decade ago to the recent demonstration of magnetization reversal by a single 40 fs laser pulse, the manipulation of spins by ultrashort laser pulses has become a fundamentally challenging topic with a potentially high impact for future spintronics, data storage and manipulation, and quantum computation. We have recently demonstrated that one can generate ultrashort and very strong (teslas) magnetic field pulses via the so-called inverse Faraday effect. Such optically induced magnetic field pulses provide unprecedented means for the generation, manipulation and coherent control of spins on very short time scales. The basic ideas behind these so-called opto-magnetic effects will be discussed and illustrated with recent results, demonstrating the various possibilities of this new field of femto-magnetism.

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Kawazoe, Tadashi, Naoki Wada, and Motoichi Ohtsu. "Emission Spectral Control of a Silicon Light Emitting Diode Fabricated by Dressed-Photon-Phonon Assisted Annealing Using a Short Pulse Pair." Advances in Optical Technologies 2014 (July 6, 2014): 1–8. http://dx.doi.org/10.1155/2014/958327.

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We fabricated a high-efficiency infrared light emitting diode (LED) via dressed-photon-phonon (DPP) assisted annealing of a p-n homojunctioned bulk Si crystal. The center wavelength in the electroluminescence (EL) spectrum of this LED was determined by the wavelength of a CW laser used in the DPP-assisted annealing. We have proposed a novel method of controlling the EL spectral shape by additionally using a pulsed light source in order to control the number of phonons for the DPP-assisted annealing. In this method, the Si crystal is irradiated with a pair of pulses having an arrival time difference between them. The number of coherent phonons created is increased (reduced) by tuning (detuning) this time difference. A Si-LED was subjected to DPP-assisted annealing using a 1.3 μm (hν=0.94 eV) CW laser and a mode-locked pulsed laser with a pulse width of 17 fs. When the number of phonons was increased, the EL emission spectrum broadened toward the high-energy side by 200 meV or more. The broadening towards the low-energy side was reduced to 120 meV.

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Sinkevicius, Giedrius, Algirdas Baskys, and Gintaras Tamošauskas. "Active Suppression of Piezoelectric Ringing in Pockels Cells for Laser Cavity Application." Symmetry 13, no. 4 (April 14, 2021): 677. http://dx.doi.org/10.3390/sym13040677.

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Pockels cells used as electro-optical modulators in high-power high-repetition lasers suffer from piezoelectric ringing phenomenon due to piezoelectric properties of the crystals. A new method for active suppression of the piezoelectric ringing in Pockels cells is proposed in this work. It is based on symmetric control of Pockels cell using burst of short positive and negative voltage pulses with the same amplitude instead of a single long pulse for light polarization modulation. Rising and falling edges of pulses of the burst induce symmetrical acoustic waves of the opposite phase and cancel the piezoelectric ringing of the crystal. A new high voltage driver capable of generating positive and negative pulses of tens of nanoseconds of 3 kV magnitude was developed for this purpose. The amplitude of laser beam intensity pulsations caused by the piezoelectric ringing can be reduced up to five times when active suppression method is used for the deuterated potassium dihydrogen phosphate (DKDP) Pockels cell. Such crystals like DKDP, LiNbO3, and LiTaO3 may benefit from the proposed method and find new use in lasers of high repetition rate where piezoelectric ringing is a major limiting factor.

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LU, CHENHUI, SHIAN ZHANG, TIANQING JIA, JIANRONG QIU, and ZHENRONG SUN. "NON-RESONANT TWO-PHOTON ABSORPTION CONTROL BY TWO TIME-DELAYED LASER PULSES." Journal of Nonlinear Optical Physics & Materials 22, no. 01 (March 2013): 1350008. http://dx.doi.org/10.1142/s0218863513500082.

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In this paper, we theoretically investigate the control of the non-resonant two-photon absorption induced by two time-delayed laser pulses, and an analytical solution for the dependence of the two-photon transition probability on the time delay and relative carrier-envelope phase of the two laser pulses is achieved. We show that the two-photon absorption can be significantly enhanced or completely suppressed by varying the time delay between the two laser pulses or their relative carrier-envelope phase. We also show that the two-photon absorption can be selectively excited when two excited states are simultaneously excited. Furthermore, we discuss the two-photon absorption control in the molecular system and analyze the effect of the absorption bandwidth on the control efficiency of the two-photon absorption.

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Wang, Rong, and Ying-Yu Niu. "Population transfer through multiple channels in two harmonic laser pulses." Journal of Theoretical and Computational Chemistry 19, no. 05 (July 24, 2020): 2050023. http://dx.doi.org/10.1142/s0219633620500236.

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The processes of population transfer in the ground electronic state of HCl molecule through the three transition schemes are investigated by numerically solving the time-dependent Schrödinger equation. Two harmonic pulses are employed to induce population transfer and the relative phase of the two pulses can control the final population distributions. In the ladder transition scheme, the variation range of the target population with the relative phase is nearly 100% which is larger than that in the multi-photon transition scheme. It is more efficient for the mixed transition scheme to control population transfer between the initial and target states by using the relative phase. Comparing with the multi-photon and ladder schemes, the transition probability of the target population is more sensitive to the two pulse amplitudes in the mixed transition scheme.

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ZVORYKIN, V. D., and I. G. LEBO. "Laser and target experiments on KrF GARPUN laser installation at FIAN." Laser and Particle Beams 17, no. 1 (January 1999): 69–88. http://dx.doi.org/10.1017/s0263034699171064.

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Multistage, e-beam-pumped, 100 J-class KrF laser installation “GARPUN” is described with the emphases to high-power laser beam control and target irradiation experiments. The ablation pressures in the megabar range were measured and hydrodynamic flow was investigated both experimentally and by numerical simulations for laser intensities up to 5×1012 W/cm2, pulse duration of 100 ns, and focal spot diameter 150 μm. Graphite-diamond phase transformation under laser loading was observed by dynamic and Raman scattering methods. Some approaches to the fast ignition inertial confinement fusion, using the simultaneous amplification of long and short laser pulses in KrF drivers, are considered.

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Lin, J., Y. Ma, R. Schwartz, D. Woodbury, J. A. Nees, M. Mathis, A. G. R. Thomas, K. Krushelnick, and H. Milchberg. "Adaptive control of laser-wakefield accelerators driven by mid-IR laser pulses." Optics Express 27, no. 8 (April 4, 2019): 10912. http://dx.doi.org/10.1364/oe.27.010912.

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Carroll, David C., Dimitri Batani, Roger G. Evans, Yannick Glinec, Christian Homann, Rashida Jafer, Satyabrata Kar, et al. "Dynamic control and enhancement of laser-accelerated protons using multiple laser pulses." Comptes Rendus Physique 10, no. 2-3 (March 2009): 188–96. http://dx.doi.org/10.1016/j.crhy.2009.03.003.

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Sun, Bangshan, Patrick S. Salter, and Martin J. Booth. "Pulse front adaptive optics: a new method for control of ultrashort laser pulses." Optics Express 23, no. 15 (July 17, 2015): 19348. http://dx.doi.org/10.1364/oe.23.019348.

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MIYAZAKI, Kenzo. "Generation and Control of High-Intensity Ultrashort Laser Pulses." Review of Laser Engineering 27, no. 5 (1999): 319–23. http://dx.doi.org/10.2184/lsj.27.319.

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GAO Hui, 高慧, 赵佳宇 ZHAO Jia-yu, and 刘伟伟 LIU Wei-wei. "Control of multiple filamentation induced by ultrafast laser pulses." Optics and Precision Engineering 21, no. 3 (2013): 598–607. http://dx.doi.org/10.3788/ope.20132103.0598.

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Journal articles on the topic 'Control with laser pulses'

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